The present invention relates to a semiconductor device and, more particularly, to a method for manufacturing a zirconium oxide film for use in a semiconductor device by using Zr(OC(CH3)3)4 (zirconium tetra-tert-butoxide) as a zirconium oxygen source material in place of conventional ZrCl4.
Generally, in a semiconductor memory device, various dielectric materials are used for a gate oxide film and a capacitor thin film so that dielectric properties mainly affect derivability of the semiconductor memory device.
With high integration and high speed of the semiconductor memory device, research has been undertaken for application of a titanium oxide (TiO2) or an aluminum oxide (Al2O3) as the dielectric material in place of a conventional silicon oxide (SiO2).
A zirconium oxide (ZrO2) film has been applied to the gate oxide film of the semiconductor memory devices with high integration. The zirconium oxide is formed by using an atomic film deposition (ALD) technique. Conventionally, ZrCl4 and vaporized water (H2O) are used as a zirconium source material and an oxygen source material, respectively.
In more detail, a conventional manufacturing method for forming the zirconium oxide film includes the steps of setting a wafer in a reaction chamber; heating the wafer up to a predetermined temperature; supplying the zirconium source material of ZrCl4 into the reaction chamber; purging out unreacted ZrCl4; supplying the oxygen source material of vaporized H2O into the chamber; and purging out unreacted vaporized H2O. This is one cycle for depositing the zirconium oxide film. By repeating this cycle, the intended thickness of the zirconium oxide film is obtained.
However, since the conventional method utilizes ZrCl4 as the zirconium source material, the zirconium oxide film of the prior art has a disadvantage in that there are chlorines (Cl) remaining in the zirconium oxide film. As a result, an electrical property of the device is degraded and an agglomeration of the zirconium oxide film is apt to occur. In addition, the ZrCl4 is characteristically in a solid state at room temperature and it is melted at a temperature of 437xc2x0 C. and a pressure of 25 atm. Therefore, it is difficult to supply the ZrCl4 into the reaction chamber in a gaseous state.
It is, therefore, an object of the present invention to provide a method for manufacturing a zirconium oxide film by 25 using Zr(OC(CH3)3)4 (zirconium tetra-tert-butoxide) as a zirconium source material instead of conventional ZrCl4, thereby inhibiting the remainder of chlorine in the zirconium oxide film.
In accordance with one aspect of the present invention, there is provided a method for manufacturing a zirconium oxide film for use in a semiconductor device by using an atomic layer deposition (ALD), the method comprising steps of a) setting a wafer in a reaction chamber; b) supplying a zirconium source material of Zr(OC(CH3)3)4 into the reaction chamber; c) purging out unreacted Zr(OC(CH3)3)4; d) supplying an oxygen source material into the reaction chamber; and e) purging out unreacted oxygen source material.
In accordance with another aspect of the present invention, there is provided a method for manufacturing a zirconium oxide film for use in a semiconductor device by using an atomic layer deposition (ALD), the method comprising steps of a) setting a wafer in a reaction chamber; b) supplying a zirconium source material of Zr(OC(CH3)3)4 into the reaction chamber; c) purging out unreacted Zr(OC(CH3)3)4; d) supplying nitrogen species gas into the reaction chamber; and e) purging out unreacted nitrogen species gas.